What is the minimum frequency with which a 300-turn,flat coil of cross sectional area 370 cm² can be rotated in a uniform 25-mT magnetic field if the maximum value of the induced emf is to equal 8.6 V? A)0.20 Hz B)2.2 Hz C)4.9 Hz D)31 Hz E)0.031 Hz

Question

Quizplus · Accepted Answer

We can use the equation for emf induced in a rotating coil:

Emf = NBAω

Where N = 300 (number of turns), B = 25 mT = 0.025 T (magnetic field), A = 370 cm^2 = 0.037 m^2 (cross-sectional area) and emf = 8.6 V. Solving for ω (angular velocity):

ω = Emf / (NBA)

ω = 8.6 / (300 x 0.025 x 0.037)

ω = 4.93 rad/s

The frequency (f) of rotation can be found using:

f = ω / (2π)

f = 4.93 / (2π)

f ≈ 0.784 Hz

Therefore, the minimum frequency with which the coil should be rotated is approximately 0.784 Hz, which is closest to choice C (4.9 Hz) among the given options.

What Is the Minimum Frequency with Which a 300-Turn,flat Coil